1. Field of the Disclosure
The following disclosure is directed to scintillation articles, and more particularly a PMT assembly and cap assembly that are removable from a PMT housing.
2. Description of the Related Art
Radiation detector devices are used in a variety of industrial applications, for example, well logging in the oil and gas industry. Typically, the detectors have scintillator crystals made of an activated sodium iodide or other material that is effective for detecting certain types of radiation. Because the scintillator crystals are sensitive components, they are generally enclosed in casings or sleeves. The casings can include a window to permit radiation-induced scintillation light to pass out of the crystal package to a light-sensing device such as a photomultiplier tube. The photomultiplier tube converts the light photons emitted from the crystal into electrical pulses, which are shaped and digitized by associated electronics and may be registered as counts that are transmitted to analyzing equipment.
In certain applications, such as the well logging industry, scintillation detectors are useful because they are capable of measuring the radiation, such as gamma rays and neutrons emitted from surrounding rock strata. In fact, scintillation detectors can be used in drilling apparatuses themselves, giving rise to the common practice of measurement while drilling (MWD) (or logging while drilling). Nonetheless, MWD applications often take place in severe environments characterized by large amounts of heat, vibration and shock. Vibration and shock can cause the detector and/or the PMT assembly to malfunction or fail.
Accordingly, the industry continues to need improvements in scintillation articles and PMT assemblies, particularly designed to be used in the harsh environments of industrial applications.